Introduction: Why Your Shed Base Deserves More Attention
Most people get shed fever and skip straight to the fun bit: choosing the size, style, and colour. But here’s the thing: no matter how beautiful your shed is, if the base is wrong, the whole thing’s doomed. Tilted floors, doors that won’t shut, puddles where your feet should be... sound familiar? That’s the work of a poor foundation.
Think of your shed base like a cuppa...it’s the thing that holds everything together. A proper, level, well-drained foundation keeps your shed standing proud through Norfolk’s wind, rain, and occasional sideways hail. It’s not glamorous, but it’s absolutely essential.
The Science Beneath Your Shed
Before you even think about laying your first slab, it helps to understand what’s actually going on under your shed. A base isn’t just a flat surface, it’s a stabiliser. Your shed might only weigh a few hundred kilos, but that weight gets concentrated at pressure points on the corners and along the joists. Over time, if the soil beneath shifts, the whole structure starts to move like a slow-motion seesaw.
That’s why a solid sub-base matters just as much as the visible top layer. Compacting the ground before laying gravel or slabs locks particles together, reducing future sinking. In frost-prone areas, particularly around Norfolk’s heavier clay zones, digging slightly deeper (100–150mm) and laying a crushed-stone sub-base helps counter frost heave...the annoying winter swelling that can push your shed floor out of alignment.
Think of it this way: you’re not just building a base for today; you’re laying a foundation that should hold up through Norfolk’s winter rains, spring thaws and the odd “horizontal” April shower.
Common Shed Base Types Explained
There’s no one-size-fits-all solution. The best base depends on your soil, budget, and shed type. The four main options are:
- Gravel bases – Affordable and quick to install.
- Slab bases – Neat, stable and tidy.
- Concrete bases – Heavy-duty and permanent.
- Timber or plastic grid bases – Lightweight and versatile.
At Norfolk Sheds, we’ve seen every combination imaginable. Some look like works of art. Others… not so much. The trick is matching the right base to your specific ground.
Gravel Bases: The Flexible Favourite
A good gravel base isn’t just a pile of stones, it’s a drainage system in disguise. Done right, it channels moisture away from your shed floor instead of trapping it underneath. Start with a levelled bed of compacted hardcore (type 1 MOT or crushed concrete) about 75–100mm deep. Add a layer of sharp sand or pea shingle on top for levelling.
The beauty of gravel is how forgiving it is. If your ground shifts slightly (and on Norfolk clay, it almost certainly will)...gravel adapts. It allows movement without cracking like concrete or rocking like loose slabs. For coastal gardens or plots with poor drainage, a gravel base can genuinely extend the lifespan of your shed.
Tip: lay a permeable weed membrane before filling the frame with gravel. It’ll stop weeds sneaking through but still allow water to drain freely.
If you’re installing something like a DIY BBQ kitchen shelter, a simple gravel foundation is usually enough to keep it level and dry.
Slab Bases: The Traditional All-Rounder
Paving slabs remain a solid middle ground between flexibility and permanence. But many homeowners lay them straight on soil or soft sand and then wonder why their shed wobbles after the first wet winter. The trick is to create a compacted sub-base layer underneath, just like with gravel. That 50–75mm of crushed stone gives slabs the stability they need.
Leave tiny 10mm gaps between slabs filled with coarse sand as this helps with drainage and prevents frost cracking. In exposed parts of Norfolk (coastal or windy fields), anchoring the corners of the shed with metal pegs or ground screws gives even more stability.
It’s this balance, firmness with breathability, that makes slab bases such a favourite for sheds up to 10x8ft.
Concrete Bases: The Heavy-Duty Option
A proper concrete base is the shed world’s equivalent of a fortress, but even fortresses need good ground prep. The most common mistake we see in Norfolk? Pouring concrete directly onto soil. Within a year, you’ll see cracks, slumping and frost damage. The right way is a two-layer system: first, 100mm of compacted hardcore; then your concrete slab (at least 100mm thick, ideally with reinforcing mesh).
If your garden is prone to puddles or standing water, consider adding a slight gradient (1:80) so rain runs away naturally. For extreme cases, edge the slab with drainage gravel to help water escape.
Once set, a concrete base can last decades, making it ideal for larger ready made sheds or workshops that need rock-solid stability year-round.
Wooden & Plastic Bases: Quick and Simple Solutions (EcoBase FastFit & Gorilla Base)
Not everyone wants to spend a weekend with concrete and spirit levels. If you prefer something quicker (and frankly cleaner), modular shed base systems are your best friend. Norfolk Sheds offers two brilliant options designed to make installation almost foolproof:
EcoBase FastFit Shed Base: An eco-friendly, lightweight grid system made from recycled plastic. It clips together in minutes, forms a solid, permeable foundation, and doesn’t need cement. It’s perfect for smaller sheds, greenhouses, and storage units, especially in gardens where you want minimal ground disturbance. The honeycomb design distributes weight evenly and keeps airflow beneath your shed floor, which means no soggy timber and no rot.
Gorilla Base: The heavy-duty cousin of the EcoBase. These interlocking tiles are strong enough to support larger sheds, cabins, or workshops, offering the same drainage benefits but with reinforced structure. Ideal for heavier sheds, Gorilla Base gives you concrete-level stability without the mess or permanence.
Add a breathable weed membrane underneath either system, fill the gaps with pea gravel if needed, and you’ll have a dry, raised, low-maintenance platform that’s ready for action.
Norfolk Soils and Local Challenges
Building in Norfolk isn’t quite the same as building elsewhere. Our region’s soil varies wildly: heavy clay in the south, sandy coastlines near Cromer and Great Yarmouth, and chalky subsoil inland.
Clay expands and contracts with moisture, which means a shed can shift if it’s not supported. In contrast, sandy soil drains quickly but erodes easily.
That’s why a proper base is crucial here. The Norfolk County Council’s drainage advice highlights the need for sustainable ground management. Good drainage keeps water away from your shed’s base, preventing rot and frost damage.
Case Study: Norwich Town Garden Installation
Lucy and Ben from Norwich wanted a neat 8x6ft storage shed at the bottom of their terraced garden. Their problem? A slight slope and patchy clay soil.
They chose an EcoBase FastFit system for its quick install and drainage benefits. In an afternoon, they’d clicked it together, levelled it, and placed their shed right on top. They sealed the shed with Norfolk Sheds’ paint range and added guttering to direct rain away.
A year later, the base is still rock solid, and they never had to mix a single bag of cement.
Case Study: Rural Norfolk Shed on Clay Ground
Out near Dereham, Alan needed a workshop for his tractor tools. His plot was uneven and held water after heavy rain.
He dug out the area, filled it with compacted hardcore, and laid a Gorilla Base grid before installing a heavy-duty ready-made shed. The raised system kept his floor perfectly dry, even during a brutal Norfolk winter.
He finished it off with a protective coat from Norfolk Sheds’ paint range. Proof that a strong foundation and good paintwork can outsmart any weather.
Common Mistakes When Laying a Base
- Skipping the membrane: weed roots and moisture creep up from below.
- Not compacting soil: the base sinks unevenly, warping the floor.
- Ignoring slope: water collects under the shed instead of draining away.
- Using untreated timber: rot sets in quickly.
- Pouring concrete directly on soil: cracks appear within months.
Avoiding these pitfalls means your shed lasts years longer.
The Role of Drainage and Weatherproofing
It’s easy to underestimate how much water your garden sheds collect. A week of steady Norfolk rain can dump hundreds of litres around the base. Without drainage, that water lingers, seeping into corners, warping floors, and inviting rot.
Good base design includes edge drainage: a 10–15cm gravel border around your base helps water escape and stops mud splashing up onto the timber. For concrete or slabs, tilt the surface ever so slightly...a gradient of 1cm per metre is enough to let rain flow off.
Then, finish the job with a quality timber sealant from Norfolk Sheds’ paint range. That top coat protects your structure where it’s most vulnerable — the first few inches above the base.
Maintaining and Protecting Your Base Over Time
Even the best foundations need care. Sweep debris away, check corners after heavy rain, and make sure nearby plants don’t block airflow.
A fresh coat of preservative every year protects not just the walls, but the edges nearest the base where rot loves to start. With the right care, your foundation can last decades.
FAQs
Do I need a base for my shed?
Yes, absolutely. Every shed needs a solid foundation. Without one, your floor will absorb moisture, sag over time, and eventually rot. Even a simple gravel pad or an EcoBase FastFit will give your shed the stability it needs and protect it from Norfolk’s famously damp winters.
What’s the best base for clay soil in Norfolk?
For heavy clay soil, a concrete slab or Gorilla Base system works best. Both spread the load evenly and prevent sinking when the ground gets soft after heavy rain.
How thick should a concrete base be?
10–15cm is ideal for most standard sheds. For heavier cabins or garden offices, go up to 20cm and reinforce with mesh for extra strength.
Can I put a shed on decking or grass?
Decking can work if it’s treated, ventilated, and strong enough to bear the load. Grass, however, is a no-go as it traps moisture, causes rot, and attracts pests.
Do I need planning permission for a shed base?
Usually not. The base is part of your permitted development rights as long as your shed meets Planning Portal height and size limits. Always double-check if you live in a conservation area, though.
Should I insulate under the shed floor?
Yes, especially if you’re using your shed as a workspace, home office, or gym. Rigid insulation boards or foil-backed panels keep out the chill and help prevent condensation.
Can I reuse an old base?
If it’s solid, level, and crack-free, absolutely. Just clean it thoroughly and check for dips or movement before placing a new shed on top.
How do I stop water pooling around my base?
Add gravel borders or drainage channels so rainwater runs away instead of pooling. Norfolk’s flat landscapes can trap water easily, so a small gradient makes all the difference.
How long does a shed base last?
A properly built concrete base can last over 25 years. Gravel or slab bases usually last 10–15 with light maintenance, and modular bases like EcoBase FastFit or Gorilla Base will easily last a decade or more if kept clear of debris.
Should I paint or treat my shed after the base is in?
Definitely. The first few inches above the base are most exposed to moisture. Seal them using Norfolk Sheds’ paint range to keep timber protected year-round.
Ready to lay the perfect foundation?
Before you start hammering panels together, make sure your foundation is sorted. Norfolk Sheds has everything you need for lightweight, eco-friendly builds to heavy-duty workshops and cabins.
A good base doesn’t just hold your shed...it holds your peace of mind, your tools, and your Sunday afternoons.